Thermal management is a leading contributor to an LED lighting “cost penalty” that is limiting global market acceptance of the technology. Unlike incandescent light sources, which remove most of the waste heat by radiating in an infrared region, waste heat generated by LEDs must be removed via conduction and convection. Convection is often not possible because encapsulation prevents exposing a heated area to a medium that convects heat.
As the LED lighting industry seeks to generate the required luminous flux of each device, it has become standard practice to use either a single high-power packaged LED chip or a packaged LED array. In either case, the heat generated by the device is seemingly accepted as a fact of life by the industry that then focuses its investment on materials that are usable to dissipate that heat—sometimes in the device itself, sometimes in the LED luminaire, and sometimes in both.